Industrial communication networks - Fieldbus specifications - Part 5-26: Application layer service definition - Type 26 elements

IEC 61158-5-26:2023 provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 26 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life.
This document defines in an abstract way the externally visible service provided by the Type26 fieldbus application layer in terms of:
an abstract model for defining application resources (objects) capable of being manipulated by users via the use of the FAL service;
the primitive actions and events of the service;
the parameters associated with each primitive action and event, and the form which they take; and
the interrelationship between these actions and events, and their valid sequences.

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 5-26: Définition des services de la couche application - Éléments de type 26

L'IEC 61158-5-26:2023 fournit des éléments communs pour les communications de messagerie prioritaires et non prioritaires élémentaires entre les programmes d’application des environnements d’automatisation et le matériel spécifique au bus de terrain de type 26. Le terme "prioritaire" signale l’existence d’une fenêtre temporelle dans laquelle une ou plusieurs actions spécifiées doivent être réalisées, avec un niveau de certitude défini. Si les actions spécifiées ne sont pas réalisées dans la fenêtre temporelle, les demandes d’action risquent d’être rejetées, avec les risques que cela comporte pour les équipements, les installations et éventuellement la vie humaine.
Le présent document définit de manière abstraite le service, visible par un observateur extérieur, assuré par la couche application de bus de terrain de type 26, en matière:
de modèle abstrait visant à la définition des ressources d’application (objets) qui peuvent être manipulées par des utilisateurs utilisant un service FAL;
d’événements et d’actions liés aux primitives du service;
de paramètres associés à chaque événement et action de primitive, ainsi que de forme prise par ces paramètres; et
d’interaction entre ces événements et ces actions, ainsi que de séquences valides desdits événements et actions.

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IEC 61158-5-26

Edition 2.0 2023-03

Industrial communication networks – Fieldbus specifications –
Part 5-26: Application layer service definition – Type 26 elements

IEC 61158-5-26:2023-03(en)

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IEC 61158-5-26


Edition 2.0 2023-03



Industrial communication networks – Fieldbus specifications –

Part 5-26: Application layer service definition – Type 26 elements




ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-6581-9

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® Registered trademark of the International Electrotechnical Commission

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– 2 – IEC 61158-5-26:2023 © IEC 2023
1 Scope . 8
1.1 General . 8
1.2 Specifications . 9
1.3 Conformance . 9
2 Normative references . 9
3 Terms, definitions, symbols, abbreviated terms and conventions . 11
3.1 Terms and definitions from other ISO/IEC standards . 11
3.1.1 Terms and definitions from ISO/IEC 7498-1 . 11
3.1.2 Terms and definitions from ISO/IEC 8822 . 11
3.1.3 Terms and definitions from ISO/IEC 9545 . 11
3.1.4 Terms and definitions from ISO/IEC 8824-1 . 12
3.2 Fi

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